Answer:
Use the normal distribution if the population standard deviation is known.
Use the student's t distribution when the population standard deviation is unknown.
Explanation:
A mound-shaped distribution refers to the normal distribution.
A good sample size for testing against the normal distribution should be
n >= 30.
The condition for the sample size is satisfied.
However, we are not given the population standard deviation, therefore it is assumed to be unknown.
Therefore the student's t distribution should be used.
So the formula for the circumference of a circle is π x diameter
Since we know the the circumference already, we just divide that by π:
12π / π = 12
Now we halve the diameter to get the radius:
12 / 2 = 6
The area of a circle is π x radius²
So the area is:
·π x 6² = 36π· (or 113 not in terms of π)
The cook do not have enough flour. He only has 2.67 cups of flour while the recipe needs 2.75 cups of flour. Therefore, he needs 0.08 more cups of flour in order to have enough for the recipe. Hope this answers the question. Have a nice day.
